Torque output shaft and actuating device for transmission system

Abstract

The invention relates to a torque output shaft (50) for an actuating device of a transmission system comprising: - a gear ring (51) having a first axis of revolution (Y); - a cylindrical sleeve (52) concentric with the first axis of revolution (Y) and supporting at one of its ends the gear ring, and - an actuating cam (20) arranged on the other end of the cylindrical sleeve (52) and integral in rotation with the cylindrical sleeve, the actuating cam (20) comprising in a section plane perpendicular to the first axis of revolution (Y) a profile having a substantially triangular shape. (Fig. 3)

Description

Title of the invention: Torque output shaft and actuating device for transmission system Technical field of the invention

[0001] The present invention relates to the field of actuating devices for transmission systems, and more particularly to the torque output shaft included in such an actuating device.

[0002] The actuating device is for example inserted into a transmission system of the connecting clutch type interposed between the output of a speed reducer and the wheel of the vehicle. Alternatively, the actuating device is for example used in addition to an actuating fork for changing a gear ratio within a gearbox. The transmission system can transmit for example a torque or a movement, state of the prior art

[0003] In the case of a multi-ratio speed reducer or a gearbox, the actuating device allows for a clutch between an axially movable sliding gear and at least one idler gear, generally two idler gears. The idler gear(s) are mounted freely around a driven shaft and the sliding gear is coupled in rotation with this driven shaft. Thus, the clutch of an idler gear allows this idler gear to be secured in rotation with this driven shaft. The axial movement of the sliding gear is placed under the control of a selection fork of at least one ratio, generally two ratios. Such clutch is carried out during an angular correspondence between the clutch teeth of the sliding gear and the clutch teeth of one of the idler gears.

[0004] Such actuating devices may be used in certain robotic gearboxes, in which the gear selection is controlled by an actuating device such as an electromechanical actuator. Such an actuating device is known from document EP1520127. In this gearbox, the electromechanical actuator uses a rotatable actuator rod, which is provided at its end with an eccentric pin for cooperation with the movable sliding gear. A rotation of the actuator rod through 180° by means of an electric motor from the rotational position corresponding to one axial end position of the movable sliding gear to a rotational position corresponding to the other axial end position of the movable sliding gear leads to a coupling or a discoupling of the dog clutch. The sliding movement of the eccentric pin on the bearing surface of the movable sliding gear is carried out under force.Since the diameter of the eccentric pin is small, the contact pressure at the pin is . centric is high. This generates friction at the support interface and consequently wear of this support interface.

[0005] Another disadvantage of this actuating device is that it is necessary to rotate the actuator rod 180° to reach the two extreme actuating positions. The actuating time is therefore extended. Precise angular positioning of the actuator rod is also necessary to ensure that the extreme position located at 180° is maintained. Consequently, the actuating device must include a precise angular position sensor. Finally, the two extreme actuating positions are not stable because an angular variation of a few degrees on the actuator rod generates a movement of the movable slider with the risk of disengaging the gear ratio.

[0006] Also, it is necessary to have precise guidance of the actuator rod within the electromagnetic actuator to facilitate the control of the eccentric spindle. Presentation of the invention

[0007] The main object of the present invention is thus a torque output shaft for an actuating device of a transmission system comprising:

[0008] - a gear ring having a first axis of revolution Y;

[0009] - a cylindrical sleeve concentric with the first axis of revolution Y and supporting at one of its ends the gear ring, and

[0010] - an actuating cam arranged on the other end of the cylindrical sleeve and integral in rotation with the cylindrical sleeve,

[0011] the actuating cam comprising in a section plane perpendicular to the first axis of revolution Y a profile defined by at least three actuating faces produced in the form of a cylinder portion, the three centers of the cylinder portions forming a triangle.

[0012] The geometry of the contact zones of the actuating cam with the associated transmission system uses large diameter cylinder portions, thus making it possible to reduce the contact pressure with the receiving housing of the transmission system in which the actuating cam is inserted. This limits wear at the contact zones.

[0013] Preferably, the cylindrical sleeve may comprise a cylindrical guide surface arranged to guide the torque output shaft within the actuating device.

[0014] Advantageously, the three cylinder portion centers can form an isosceles triangle and the main vertex of the isosceles triangle coincides with the first axis of revolution Y of the torque output shaft.

[0015] According to one embodiment of the invention, the actuating cam, the sleeve cy The lindrique and the gear ring form a single-piece torque output shaft made of the same material. This solution is economical and ensures high precision in the positioning of the actuating cam relative to the cylindrical sleeve of the torque output shaft.

[0016] According to one variant, the material may be an injected plastic material, for example polyamide.

[0017] According to another variant, the material may be a sintered metal, for example hot-compressed metal powder.

[0018] According to another embodiment of the invention, the actuating cam can be attached to the cylindrical sleeve, for example riveted or screwed or force-fitted or welded or secured in rotation by form fitting.

[0019] Advantageously, the actuating cam can be housed in a cavity formed on the end of the cylindrical sleeve.

[0020] According to one embodiment of the invention, the meshing ring gear may comprise an internal toothing, the internal toothing forming a recess in the torque output shaft. The recess has the advantage of reducing the thickness of the part which becomes easier to inject into plastic molding or to sinter.

[0021] According to another embodiment of the invention, the meshing ring gear may comprise meshing pads distributed angularly around the first axis of revolution Y, each of the meshing pads being circular in shape along an axis parallel to the first axis of revolution Y.

[0022] According to another embodiment of the invention, the meshing ring can comprise orifices capable of receiving meshing studs.

[0023] According to another embodiment of the invention, the gear ring may comprise external teeth.

[0024] This torque output shaft thus has the advantage of being economical, of guaranteeing good dimensional precision of the actuating cam and of having precise guidance of the actuating cam within the actuating device.

[0025] The invention also relates, according to another of its aspects, to an actuating device for a transmission system, comprising:

[0026] - a fixing casing;

[0027] - an electric motor comprising a stator fixed relative to the fixing casing, a rotor and a rotor shaft pivoting around a first axis of revolution Y;

[0028] - a speed reduction device of the cycloidal reducer type linked to cinema- tically to the rotor shaft of the electric motor, the speed reduction device comprising an eccentric bearing fitted onto the rotor shaft, the center of the eccentric bearing defined by a second axis of revolution Y2 is radially eccentric by relation to the first axis of revolution Y;

[0029] - a torque output shaft incorporating all or part of the characteristics of previously mentioned, the torque output shaft being guided in rotation along the first axis of revolution Y relative to the fixing housing by means of the cylindrical sleeve;

[0030] - a receiving member of the eccentric bearing having a cycloidal movement within the speed reduction device and which is kinematically linked to the torque output shaft;

[0031] and wherein the fixing housing comprises an opening arranged for the passage of the torque output shaft, the actuating cam projecting axially relative to the opening.

[0032] This actuating device thus has the advantage of being economical and of guaranteeing precise guidance of the actuating cam relative to the casing of the actuating device. The cycloidal reducer type speed reduction device has the advantage of having a high speed ratio between the rotor shaft and the torque output shaft in a reduced size.

[0033] Advantageously, the cylindrical guide surface of the torque output shaft can be inserted into a bore of the fixing housing which opens into the opening.

[0034] Preferably, the second axis of revolution Y2 is eccentric relative to the first axis of revolution Y by an eccentricity distance of between 1 and 20 mm.

[0035] Advantageously, the torque output shaft can be arranged to pivot according to three adjacent angular sectors, a first angular sector, a second angular sector which is adjacent to the first angular sector, a third angular sector which is adjacent to the second angular sector.

[0036] This actuating device makes it possible, in particular thanks to the first angular sector and the third angular sector, to have two stable extreme actuating positions because an angular variation of a few degrees on the output shaft does not generate any movement of the axial sliding member. As the two extreme actuating positions are stable, it is possible to cut off the electrical power supply within the actuating device, thus reducing the electrical consumption of the vehicle.

[0037] The angle value of the second angular sector is strictly less than 180°. Thus, the angular movement of the torque output shaft is reduced, which has the consequence of reducing the actuation time.

[0038] Preferably, the rotor shaft of the electric motor can be guided relative to the fixing housing using bearings along the first axis of revolution Y and has a shaft part eccentric along the second axis of revolution Y2 and which supports the eccentric bearing.

[0039] According to one embodiment of the invention, the gear ring can comprise internal teeth, the receiving member of the eccentric bearing then being a toothed wheel inserted into the internal teeth, and said toothed wheel comprises:

[0040] - a central orifice receiving the eccentric bearing,

[0041] - an external toothing which meshes with the internal toothing of the crown of meshing, and

[0042] - a series of meshing studs distributed angularly around the central orifice which project axially parallel to the first axis of revolution Y and which cooperate with holes formed in a support plate attached to the fixing casing.

[0043] Preferably, the meshing pads can be distributed around the second axis of revolution Y2.

[0044] Advantageously, the eccentric bearing may be a ball bearing or a needle bearing which exerts radial support of the toothed wheel on the internal teeth of the torque output shaft in order to generate a rotating radial eccentric movement of the toothed wheel, the inner ring of the eccentric bearing being linked in rotation to the rotor shaft.

[0045] Preferably, the outer teeth of the toothed wheel having a rotating radial eccentric movement can mesh with at least one tooth of the inner teeth of the torque output shaft.

[0046] According to another embodiment of the invention, the meshing ring gear may comprise meshing studs distributed angularly around the first axis of revolution Y, the receiving member of the eccentric bearing then being a flat plate kinematically linked to the torque output shaft, and said flat plate comprises:

[0047] - a central orifice receiving the eccentric bearing,

[0048] - a series of holes distributed angularly around the central orifice in which the gear pads of the torque output shaft are inserted, and,

[0049] - an external toothing arranged to cooperate by a rolling movement with a series of bosses distributed angularly on the mounting housing.

[0050] Advantageously, the eccentric bearing may be a ball bearing or a needle bearing which exerts radial support of the external teeth of the flat plate on at least one boss of the fixing casing in order to generate a rotating radial eccentric movement of the flat plate, the inner ring of the eccentric bearing being linked in rotation to the rotor shaft.

[0051] Preferably, the holes of the flat plate having a rotating radial eccentric movement can rotate the meshing pads of the torque output shaft.

[0052] The actuating device according to the invention may have one or other of the characteristics described below combined with each other or taken independently. each other:

[0053] - the actuating device is attached to a housing of the transmission system;

[0054] - the angle value of the first angular sector is greater than 3°;

[0055] - the angle value of the second angular sector is between 20° and 179°;

[0056] - the angle value of the third angular sector is greater than 3°;

[0057] - the angle value of the first angular sector is identical to the angle value of the third angular sector;

[0058] - the angle value of the first angular sector is different from the angle value of the third angular sector;

[0059] - the angle value of the second angular sector is greater than the angle value of the first angular sector;

[0060] - the angle value of the second angular sector is greater than the angle value of the third angular sector.

[0061] The invention also relates, according to another of its aspects, to a transmission system comprising:

[0062] - a transmission drive shaft comprising a first external spline;

[0063] - a driven transmission shaft coaxial with the driving shaft comprising a second external groove;

[0064] - an actuating device incorporating all or part of the characteristics of previously mentioned, in which the actuating cam of the torque output shaft is inserted into an axial sliding member having a revolution shape which partially surrounds the driving shaft and the driven shaft,

[0065] the axial slider comprising at least a first internal connection groove arranged to rotate the driving shaft and a second internal connection groove arranged to rotate the driven shaft, and the axial slider is axially movable along a main axis X perpendicular to the first axis of revolution Y between two extreme positions when the torque output shaft pivots along the entire second angular sector.

[0066] This transmission system architecture has the advantage of being compact and will be suitable for any integration within a speed reducer of a hybrid or electric motor vehicle to disconnect the transmission of torque from the driving shaft, for example the output shaft of a speed reducer, to the driven shaft, for example the wheel of a vehicle. When the reversible electric machine associated with the speed reducer is inactive, there is no point in leaving said electric machine connected to the wheel of the vehicle. In this embodiment of the invention, the transmission system is an improved connecting clutch between two driving and driven shafts.

[0067] Advantageously, within this transmission system, the axial slider can remain axially stationary in a first extreme position when the rotation of the torque output shaft is in the first angular sector,

[0068] the axial sliding member can remain axially stationary in a second extreme position when the rotation of the torque output shaft is located in the third angular sector, and

[0069] the first and second internal splines are engaged respectively in the first external spline of the driving shaft and the second external spline of the driven shaft when the axial slider is in one of the two extreme positions, this extreme position being called the second extreme coupling position.

[0070] This transmission system architecture makes it possible, in particular thanks to the first angular sector and the third angular sector, to have two stable extreme actuation positions because an angular variation of a few degrees on the output shaft does not generate any movement of the axial sliding gear. As the two extreme actuation positions are stable, it is possible to cut off the electrical power supply within the transmission system, thus reducing the electrical consumption of the motorized vehicle.

[0071] Preferably, the second internal connection spline can be disengaged from the second external spline of the driven shaft when the axial slider is in the other of the two extreme positions, this extreme position being called the first extreme uncoupling position.

[0072] Conversely, the first internal connecting spline can be disengaged from the first external spline of the driving shaft when the axial slider is in the other of the two extreme positions, this extreme position being called the first extreme uncoupling position.

[0073] Advantageously, the axial slider may comprise a housing for receiving the actuating cam of the torque output shaft formed by two surfaces parallel to each other and perpendicular to the main axis X.

[0074] Preferably, the actuating cam may have two contact zones bearing on the parallel surfaces of the housing for receiving the axial slider, the bearing width along the main axis X separating the two contact zones is constant over the three angular sectors of rotation of the output shaft. The precision of the actuation is thus improved.

[0075] Advantageously, an operating clearance can be defined between the bearing width of the actuating cam and the distance axially separating, along the main axis X, the two parallel surfaces of the receiving housing, the operating clearance is constant over the three angular sectors of rotation of the output shaft. The operating clearance is of the order of 0.1 mm to 0.6 mm. The precision of the actuation is thus improved.

[0076] Preferably, the axial slider may be a part of revolution around the main axis X, the receiving housing being an annular groove. A relative rotational movement along the main axis X between the axial slider and the actuating cam is possible.

[0077] Advantageously, the second internal connection groove of the axial slider can be produced in the form of a series of internal grooves spaced axially at a regular pitch, for example four internal grooves spaced axially at a pitch of between 3 and 15 mm.

[0078] Preferably, the second internal groove can be produced in the form of a series of internal grooves added and welded onto the main body of the axial slider.

[0079] Advantageously, the actuating cam may have a symmetrical actuating profile whose axis of symmetry passes through the bisector of the isosceles triangle, the bisector of the isosceles triangle corresponding to the middle of the second angular sector. The actuating cam thus has a symmetrical profile passing through the first axis of revolution Y.

[0080] According to a variant, the actuating cam may comprise three actuating faces produced in the form of a cylinder portion, the three cylinder portion centers forming an equilateral triangle, one of the vertices of the equilateral triangle being coincident with the first axis of revolution Y of the torque output shaft.

[0081] According to another variant, the actuating cam may comprise three actuating faces made in the form of a cylinder portion, the three cylinder portion centers forming a right-angled isosceles triangle, the main vertex of the right-angled isosceles triangle being coincident with the first axis of revolution Y of the output shaft. With this geometry in the form of a right-angled triangle, the rotation along the first axis of revolution Y of the actuating cam is only 90° to reach the two extreme positions. More precisely, the second angular sector has an angle value of 90°.

[0082] Advantageously, at least two actuating faces of the actuating cam can be connected to each other by a cylindrical connecting face with a radius smaller than the radius of the cylinder portions, the connecting radius being between 1 and 5 mm.

[0083] According to one embodiment, the main axis X of the axial slider may intersect the first axis of revolution Y.

[0084] According to another embodiment, the main axis X of the axial slider may not intersect the first axis of revolution Y, the first axis of revolution Y being offset relative to a plane parallel to the first axis of revolution Y and passing through the main axis X of a value between 0 mm and the height of the isosceles or equilateral triangle of the actuating cam.

[0085] The invention further relates to a motorized vehicle, for example a hybrid or electric motor vehicle comprising a transmission system as mentioned above. The motorized vehicle could be an industrial vehicle. brief description of the figures

[0086] Other characteristics and advantages of the invention will emerge from reading the description which follows, and from examples of embodiment given for informational and non-limiting purposes with reference to the attached drawings on the other hand.

[0087] [Fig-1] [Fig.l] is a sectional view of a transmission system equipped with a actuating device according to a first embodiment of the invention.

[0088] [Fig.2] [Fig.2] is an exploded isometric view of the actuating device of [Fig.l],

[0089] [Fig.3] [Fig.3] is an isometric view of the torque output shaft of the actuator of [Fig.l].

[0090] [Fig.4] [Fig.4] is a sectional view of the torque output shaft of [Fig.l].

[0091] [Fig.5] [Fig.5] is a detail view of the output shaft actuating cam of torque of [Fig.3].

[0092] [Fig.6] [Fig.6] is a simplified view of the transmission system according to the first embodiment of the invention of [Fig.l].

[0093] [Fig.7] [Fig.7] is a sectional view of a torque output shaft according to a second embodiment of the invention.

[0094] [Fig.8] [Fig.8] is a sectional view of a torque output shaft according to a third embodiment of the invention.

[0095] [Fig.9] [Fig.9] is an isometric view of a torque output shaft of the actuating device according to a fourth embodiment of the invention.

[0096] [Fig. 10] [Fig. 10] is a sectional view of the actuating device according to the fourth embodiment of the invention of [Fig.9].

[0097] [Fig. 11] [Fig. 11] is a sectional view of an axial sliding gear of a transmission system according to a fifth embodiment of the invention.

[0098] The features, variants and different embodiments of the invention may be combined with each other, in various combinations, to the extent that they are not incompatible or mutually exclusive.

[0099] For clarity, identical or similar elements are identified by identical reference signs throughout the figures. DETAILED description of embodiments

[0100] In the description and the claims, the terms "external" and "internal" as well as the orientations "axial" and "radial" will be used to designate, according to the definitions given in the description, elements of the transmission system. By convention, the "radial" orientation is directed orthogonally to the main axis X of rotation of the transmission system determining the "axial" orientation and, from the inside to the outside moving away from said axis, the "circumferential" orientation is directed orthogonally to the main axis X and orthogonally to the radial direction.

[0101] Figures 1 to 6 illustrate a transmission system 1 according to a first embodiment of the invention. The transmission system 1 is here a connecting clutch between two shafts 2, 3 which is used, in a transmission chain of a motorized vehicle, for example a motor vehicle, to transmit a torque coming from a thermal or electric engine, not illustrated, to a wheel shaft 7 of the motor vehicle. Such a transmission system may, for example, be part of a secondary transmission chain capable of transmitting a torque from a secondary engine of the motor vehicle, such as a reversible electric machine, to a rear or front axle of the vehicle while a primary transmission chain is capable of transmitting a torque from a main engine, for example a thermal engine, to the wheel shafts of another axle of the vehicle.When the reversible electric machine associated with the speed reducer is inactive, there is no point in leaving the said electric machine connected to the vehicle wheel. The connection clutch is then disengaged.

[0102] The transmission system 1 is kinematically interposed between a speed reducer (not shown) and the wheel shaft 7 of the vehicle. The shaft corresponding to the output of the speed reducer is called the driving shaft 2. The driving transmission shaft 2 of the transmission system 1 comprises a first external spline 2a machined on its end.

[0103] The transmission system 1 also comprises a driven transmission shaft 3 coaxial with the driving shaft 2 comprising a second external spline 3a. In this example, the driven shaft 3 is inserted into the driving shaft 2 and guided in rotation by means of a guide bearing 4. The driven transmission shaft 3 comprises an internal torque output spline 3b linked in rotation with the wheel shaft 7 of the vehicle.

[0104] In order to actuate the transmission system 1, an electrically powered actuating device 10 is used. The actuating device 10, illustrated in [Fig.2], comprises in particular:

[0105] - a fixing casing 14,

[0106] - an electric motor 11 comprising a stator 15 fixed relative to the casing of fixing, a rotor 16 and a rotor shaft 17 pivoting around a first axis of revolution Y, and

[0107] - a speed reduction device 13 kinematically connecting the rotor shaft 17 to a 50 torque output shaft.

[0108] The torque output shaft 50 corresponds to the output member of the actuating device 10 and transmits the rotational movement of the electric motor 11 according to a suitable speed ratio. The speed reduction device 13 is of the cycloidal reducer type so that a high speed ratio exists between the rotor shaft 17 of the electric motor 11 and the torque output shaft 50.

[0109] As illustrated in [Fig.3], the torque output shaft 50 comprises:

[0110] - a gear ring 51 having a shape of revolution along the first axis of revolution Y;

[0111] - a cylindrical sleeve 52 concentric with the first axis of revolution Y and supporting at one of its ends the gear ring 51, and

[0112] - an actuating cam 20 arranged on the other end of the cylindrical sleeve 52 and rotationally fixed to the cylindrical sleeve.

[0113] The torque output shaft 50 is guided in rotation along the first axis of revolution Y relative to the fixing casing 14 by means of the cylindrical sleeve 52. The cylindrical sleeve 52 comprises a cylindrical guide surface 52a arranged to guide the torque output shaft within the actuating device 10. The fixing casing 14 comprises an opening 14c arranged for the passage of the torque output shaft 50 and the actuating cam 20, the latter projecting axially relative to the opening 14c. The cylindrical guide surface 52a of the torque output shaft is inserted into a bore 14d of the fixing casing which opens into the opening 14a.

[0114] The casing 14 is composed of a base casing 14b receiving in particular the torque output shaft 50 and an upper casing 14a supporting the electric motor 11. The base casing 14b is for example attached to a housing 9 of the transmission system 1.

[0115] In this first embodiment, the actuating cam 20, the cylindrical sleeve 52 and the meshing ring 51 form a single-piece torque output shaft made from the same material. The material is a sintered metal, for example hot-compressed metal powder.

[0116] As illustrated in [Fig.4], the gear ring 51 comprises an internal toothing 51a, the internal toothing forming a recess 51b in the torque output shaft 50. This recess 51b facilitates the sintering production process.

[0117] The speed reduction device 13 being of the cycloidal reducer type, it comprises an eccentric bearing 18 fitted onto the end of the rotor shaft 17 and a receiving member 40 of the eccentric bearing 18.

[0118] In this first embodiment, the receiving member is a toothed wheel 40 inserted into the internal toothing 51a of the torque output shaft 50.

[0119] The toothed wheel 40 comprises:

[0120] - a central orifice 40a receiving the eccentric bearing 18,

[0121] - an external toothing 40d which meshes with the internal toothing 5la of the gear ring 51, and

[0122] - a series of 40e meshing studs distributed angularly around the orifice central 40a which project axially parallel to the first axis of revolution Y and which cooperate with holes 61 formed in a support plate 60 attached to the fixing casing 14.

[0123] The eccentric bearing 18 is a ball bearing which exerts radial support of the toothed wheel 40 on the internal teeth 51a of the torque output shaft 50 in order to generate a rotating radial eccentric movement of the toothed wheel 40. The inner ring 18a of the eccentric bearing is linked in rotation to the rotor shaft 17. The center of the eccentric bearing 18 defined by a second axis of revolution Y2 is radially eccentric with respect to the first axis of revolution Y. The second axis of revolution Y2 is eccentric with respect to the first axis of revolution Y by an eccentricity distance of between 1 and 20 mm, for example 3 mm.

[0124] Since the external toothing 40d of the toothed wheel 40 has a rotating radial eccentric movement, it meshes with at least one tooth of the internal toothing 51a of the torque output shaft 50. Thus, the rotation of the rotor shaft 17 is transmitted to the torque output shaft 50 with a high speed ratio. The rotation of the actuating cam 20 of the torque output shaft 50 is therefore electrically controlled by the electric machine 11.

[0125] The transmission system 1 is therefore a connecting clutch between two shafts 2, 3 controlled by the actuating device 10 whose torque output shaft 50 is inserted into an axial sliding member 30 axially movable along a main axis X perpendicular to the first axis of revolution Y. The axial sliding member 30 has the function of connecting and disconnecting the driving shaft 2 with the driven shaft 3 of the transmission.

[0126] The axial slider 30 axially movable along the main axis X comprises a housing 31 for receiving the actuating cam formed by two surfaces 32 parallel to each other and perpendicular to the main axis X. In this actuating device, the axial slider 30 moves axially according to the value Dx between two extreme positions when the actuating cam pivots around the first axis of revolution Y.

[0127] More precisely, the axial sliding gear 30 has a shape of revolution, the latter comprising at least a first internal connection groove 33 arranged to drive the driving shaft 2 in rotation and a second internal connection groove 34 arranged to drive the driven shaft 3 in rotation. The first and second internal splines 33, 34 are engaged respectively in the first external spline 2a of the driving shaft and the second external spline 3a of the driven shaft when the axial slider 30 is in one of the two extreme positions of the axial slider 30, this extreme position being called the second extreme coupling position.

[0128] The second internal connection spline 34 is disengaged from the second external spline 3a of the driven shaft 3 when the axial slider 30 is in a first extreme uncoupling position. The axial slider 30 moves axially relative to the driven transmission shaft 3 which is axially fixed. It is the rotation of the actuating cam 20 around the first axis of revolution Y which causes the axial slider 30 to move.

[0129] The axial slider 30 is driven in rotation by the driving shaft 2 via the first internal spline 33 which meshes with the first external spline 2a. Since the receiving housing 31 is made in the form of an annular groove, a relative rotational movement along the main axis X between the axial slider 30 and the actuating cam 20 is possible. In this example, the actuating cam 20 is received directly in the axial slider 30. Alternatively, the actuating cam can be received in an intermediate component kinematically linked to the axial slider.

[0130] The actuating cam 20 has two contact zones 20a, 20b bearing on the parallel surfaces 32 of the receiving housing, the bearing width L along the main axis X separating the two contact zones is constant over the entire rotation of the output shaft. To guarantee a movement of the actuating cam 20 within the annular groove without untimely friction, an operating clearance is defined between the bearing width L of the actuating cam and the distance D axially separating along the main axis X the two parallel surfaces 32 of the receiving housing.

[0131] As illustrated in [Fig.5], the actuating cam 20 comprises three actuating faces 21 made in the form of a cylinder portion, the three centers 22 of the cylinder portion form an isosceles triangle, the main vertex of the isosceles triangle being coincident with the first axis of revolution Y of the torque output shaft 50. The geometry of the contact zones 20a, 20b of the actuating cam uses large diameter cylinder portions making it possible to reduce the contact pressure with the parallel surfaces of the receiving housing. During rotation of the actuating cam, the actuating face 21 slides on one of the parallel surfaces 32.

[0132] In this first embodiment, the actuating cam 20 has a symmetrical actuating profile whose axis of symmetry passes through the bisector 37 of the isosceles triangle, the bisector of the isosceles triangle corresponding to the middle of the second angular sector a2. The isosceles triangle has a height H and a principal angle [3 for example between 45° and 150°. The actuating cam 20 thus has a symmetrical profile passing through the first axis of revolution Y.

[0133] Thanks to the particular geometry of the profile of the actuating cam, the operating clearance between the bearing width L of the actuating cam and the distance D is constant over the entire rotation of the output shaft. The operating clearance is of the order of 0.1 mm to 0.6 mm. The actuation precision is thus improved.

[0134] To ensure that the actuating cam 20 moves within the annular groove 31 without untimely friction, the actuating faces 21 of the actuating cam 20 are connected to each other by a cylindrical connecting face 23 of radius R2 smaller than the radius RI of the cylinder portions, the connecting radius being between 1 and 5 mm. During rotation of the actuating cam, the cylindrical connecting face 23 is also caused to slide on one of the parallel surfaces 32. The contact zones 20a, 20b of the actuating cam are alternately formed by an actuating face 21 and / or a cylindrical connecting face 23. The geometry of the contact zone 20a, 20b then has a radius RI or a radius R2.

[0135] In order to recenter the actuating cam 20 in the receiving housing 31, the main axis X of the axial slider 30 is not intersecting the first axis of revolution Y. For example, the first axis of revolution Y is offset relative to a plane parallel to the first axis of revolution Y and passing through the main axis X by a value of a few millimeters.

[0136] We will now describe the operation of the actuating device making it possible to move from the first extreme uncoupling position to the second extreme coupling position in a reduced actuation time.

[0137] As illustrated in [Fig.6], the output shaft 12 is arranged to pivot according to three adjacent angular sectors a1, a2, a3, a first angular sector a1, a second angular sector a2 which is adjacent to the first angular sector a1, a third angular sector a3 which is adjacent to the second angular sector a2.

[0138] Initially, the axial slider 30 is in the first extreme uncoupling position. The axial slider 30 remains axially stationary in the first extreme position when the rotation of the output shaft is located in the first angular sector. The angle value of the first angular sector al is 15°. In this first angular sector al, the axial slider 30 remains in a stable position which makes it possible to cut off the electrical power supply within the actuating device, thus reducing the electrical consumption of the vehicle.

[0139] In a second step, the axial slider 30 moves axially between the two extreme uncoupling and coupling positions when the output shaft 12 pivots along the entire second angular sector a2. The displacement Dx of the axial slider 30 is visible in [Fig.6]. The angle value of the second angular sector a2 is approximately 100°. This low angle value, less than 180°, makes it possible to reduce the actuation time.

[0140] In a third step, the axial slider 30 remains axially stationary in the second extreme position when the rotation of the output shaft is located in the third angular sector a3. The angle value of the third angular sector a3 is approximately 5°. In this third angular sector a3, the axial slider 30 remains in a stable position which makes it possible to cut off the electrical power supply within the actuating device, thus reducing the electrical consumption of the vehicle.

[0141] Thanks to the particular geometry of the profile of the actuating cam, the support width L along the main axis X separating the two contact zones 20a, 20b is constant over the three angular sectors a1, a2, a3 of rotation of the output shaft. [Fig. 6] also illustrates the different angular positions taken by the actuating cam 20 during the movement Dx of the axial sliding member 30.

[0142] We will now describe with reference to [Fig.7], a second embodiment of the invention, which differs from the previous one by a different construction of the torque output shaft 50.

[0143] In this second embodiment, the torque output shaft 50 still comprises:

[0144] - a gear ring 51 having a first axis of revolution Y;

[0145] - a cylindrical sleeve 52 concentric with the first axis of revolution Y and supporting at one of its ends the gear ring 51, and

[0146] - an actuating cam 20 arranged on the other end of the cylindrical sleeve 52 and rotationally fixed to the cylindrical sleeve.

[0147] However, the actuating cam is here attached to the cylindrical sleeve 52, by screwing. The actuating cam 20 is notably housed in a cavity 52c formed on the end of the cylindrical sleeve. A fixing screw 25 is inserted into the cylindrical sleeve along the first axis of revolution Y.

[0148] The actuating cam 20 also comprises in a section plane perpendicular to the first axis of revolution Y a profile defined by at least three actuating faces 21 produced in the form of a cylinder portion, the three centers 22 of the cylinder portions forming a triangle.

[0149] We will now describe with reference to [Fig.8], a third embodiment of the invention, which differs from the previous one by a different construction of the torque output shaft 50.

[0150] In this third embodiment, the torque output shaft 50 still comprises:

[0151] - a gear ring 51 having a first axis of revolution Y;

[0152] - a cylindrical sleeve 52 concentric with the first axis of revolution Y and supporting at one of its ends the gear ring 51, and

[0153] - an actuating cam 20 arranged on the other end of the cylindrical sleeve 52 and rotationally fixed to the cylindrical sleeve.

[0154] However, the actuating cam is here attached to the cylindrical sleeve 52 by riveting. The actuating cam 20 is notably housed in a cavity 52c formed on the end of the cylindrical sleeve. A rivet 26 is inserted into the cylindrical sleeve along the first axis of revolution Y. The recess 51b facilitates the insertion of the rivet 26 and its riveting.

[0155] The actuating cam 20 also comprises in a section plane perpendicular to the first axis of revolution Y a profile defined by at least three actuating faces 21 produced in the form of a cylinder portion, the three centers 22 of the cylinder portions forming a triangle.

[0156] We will now describe with reference to Figures 9 and 10, a fourth embodiment of the invention, which differs from the previous one by a different architecture of the speed reduction device 13 constituting the actuation device 10.

[0157] In this fourth embodiment, the actuating device 10 still has the function of connecting and disconnecting the driving shaft 2 with the driven shaft 3 of the transmission by axially moving the axial sliding member 30. This actuating device 10, illustrated in particular in [Fig. 10], comprises:

[0158] - a fixing casing 14,

[0159] - an electric motor 11 driving in rotation a rotor shaft 17 pivoting around of a first axis of revolution Y, and

[0160] - a speed reduction device 13 kinematically connecting the rotor shaft 17 to a 50 torque output shaft.

[0161] The torque output shaft 50 corresponds to the output member of the actuating device 10 and transmits the rotational movement of the electric motor according to a suitable speed ratio. The speed reduction device 13 is of the cycloidal reducer type so that a high speed ratio exists between the rotor shaft 17 of the electric motor and the torque output shaft 50.

[0162] As illustrated in [Fig.9], the torque output shaft 50 comprises:

[0163] - a gear ring 51 having a shape of revolution along the first axis of revolution Y;

[0164] - a cylindrical sleeve 52 concentric with the first axis of revolution Y and supporting at one of its ends the gear ring 51, and

[0165] - an actuating cam 20 arranged on the other end of the cylindrical sleeve 52 and rotationally fixed to the cylindrical sleeve.

[0166] In this fourth embodiment of the invention, the gear ring 51 comprises meshing pads 53 distributed angularly around the first axis of revolution Y, each of the meshing pads 53 being circular in shape along an axis parallel to the first axis of revolution Y.

[0167] The torque output shaft 50 is guided in rotation along the first axis of revolution Y relative to the fixing casing 14 by means of the cylindrical sleeve 52. The cylindrical sleeve 52 comprises a cylindrical guide surface 52a arranged to guide the torque output shaft within the actuating device 10.

[0168] The speed reduction device 13 being of the cycloidal reducer type, it comprises in particular an eccentric bearing 18 fitted onto the end of the rotor shaft 17 and a receiving member 40 of the eccentric bearing 18.

[0169] In this first embodiment, the receiving member 40 of the eccentric bearing 18 is a flat plate kinematically linked to the torque output shaft 50, and said flat plate comprises:

[0170] - a central orifice 40a receiving the eccentric bearing 18,

[0171] - a series of holes 40b distributed angularly around the central orifice in into which are inserted the meshing pads 53 of the torque output shaft 50, and,

[0172] - an external toothing 40c arranged to cooperate by a rolling movement with a series of bosses 14f distributed angularly on the fixing casing 14.

[0173] The bosses 14f are in this case obtained by molding directly into the fixing casing.

[0174] The eccentric bearing 18 is a needle bearing which exerts radial support of the external toothing 40c of the flat plate on at least one boss 14f of the fixing casing 14 in order to generate a rotating radial eccentric movement of the flat plate. The inner ring 18a of the eccentric bearing 18 is rotatably connected to the rotor shaft 17. The center of the eccentric bearing 18 defined by a second axis of revolution Y2 is radially eccentric relative to the first axis of revolution Y. The second axis of revolution Y2 is eccentric relative to the first axis of revolution Y by an eccentricity distance d of between 1 and 20 mm.

[0175] Since the holes 40b of the flat plate have a rotating radial eccentric movement, the flat plate rotates the meshing pads 53 of the torque output shaft 50. Thus, the rotation of the rotor shaft 17 is transmitted to the torque output shaft 50 with a high speed ratio. The rotation of the actuating cam 20 of the torque output shaft 50 is therefore electrically controlled by the electric machine 11.

[0176] We will now describe with reference to [Fig. 11], an axial sliding gear 30 having a high torque transmission capacity while being economical to manufacture.

[0177] In order to transmit more torque in a reduced axial size, the second internal groove 34 for connecting the axial slider is made under the form of a series of internal splines spaced axially at a regular pitch, for example four internal splines spaced axially at a pitch of between 3 and 15 mm. The second external spline 3a of the driven shaft 3 is also produced in the form of a series of internal splines spaced axially at the same regular pitch.

[0178] The second internal groove is notably produced in the form of a series of internal grooves added and welded onto the main body 33 of the axial slider 30.

[0179] The present invention cannot, however, be limited to the means and configurations described and illustrated here and it also extends to any equivalent means and configuration as well as to any technically operative combination of such means.

[0180] For example, the actuating device can be used in addition to an actuating fork for changing a gear ratio within a gearbox or participating in the actuating of a differential locking device.

[0181] All these different operating modes are available thanks to the actuation device 10 according to the invention, allowing for reduced actuation times.

Claims

Claims

1. Torque output shaft (50) for an actuating device of a transmission system comprising: - a gear ring (51) having a first axis of revolution (Y); - a cylindrical sleeve (52) concentric with the first axis of revolution (Y) and supporting at one of its ends the gear ring, and - an actuating cam (20) arranged on the other end of the cylindrical sleeve (52) and integral in rotation with the cylindrical sleeve, the actuating cam (20) comprising in a section plane perpendicular to the first axis of revolution (Y) a profile defined by at least three actuating faces (21) produced in the form of a cylinder portion, the three centers (22) of the cylinder portions forming a triangle.

2. Torque output shaft (50) according to the preceding claim, wherein the cylindrical sleeve (52) comprises a cylindrical guide surface (52a) arranged to guide the torque output shaft within the actuating device.

3. Torque output shaft (50) according to one of the preceding claims, wherein the three cylinder portion centers (22) form an isosceles triangle and the main vertex of the isosceles triangle coincides with the first axis of revolution (Y) of the torque output shaft.

4. Torque output shaft (50) according to one of the preceding claims, in which the actuating cam (20), the cylindrical sleeve (52) and the meshing ring (51) form a single-piece torque output shaft made from the same material, the material being for example an injected plastic material or a sintered metal.

5. Torque output shaft (50) according to one of claims 1 to 3, in which the actuating cam (20) is attached to the cylindrical sleeve (52), for example riveted or screwed or force-fitted or welded.

6. A torque output shaft (50) according to any preceding claim, wherein the gear ring (51) comprises an internal toothing (51a), the internal toothing forming a recess (51b) in the torque output shaft.

7. Torque output shaft (50) according to one of claims 1 to 5, in which the meshing ring (51) comprises meshing studs (53) distributed angularly around the first axis of revolution (Y), each of the meshing studs being circular in shape along an axis parallel to the first axis of revolution (Y).

8. Actuating device (10) for a transmission system (1), comprising: - a fixing casing (14); - an electric motor (11) comprising a stator (15) fixed relative to the fixing casing, a rotor (16) and a rotor shaft (17) pivoting about a first axis of revolution (Y); - a speed reduction device (13) of the cycloidal reducer type kinematically linked to the rotor shaft (17) of the electric motor (11), the speed reduction device (13) comprising an eccentric bearing (18) fitted onto the rotor shaft, the center of the eccentric bearing defined by a second axis of revolution (Y2) is radially eccentric relative to the first axis of revolution (Y); - a torque output shaft (50) according to any one of the preceding claims, the torque output shaft being guided in rotation along the first axis of revolution (Y) relative to the fixing housing (14) by means of the cylindrical sleeve (52);- a receiving member (40) of the eccentric bearing having a cycloidal movement within the speed reduction device and which is kinematically linked to the torque output shaft; and in which the fixing casing (14) comprises an opening (14c) arranged for the passage of the torque output shaft, the actuating cam (20) projecting axially relative to the opening.;

9. Actuating device (10) according to the preceding claim, in which the meshing ring (51) comprises meshing studs (53) distributed angularly around the first axis of revolution (Y), the receiving member (40) of the eccentric bearing then being a flat plate kinematically linked to the torque output shaft, and said flat plate comprises: - a central orifice (40a) receiving the eccentric bearing (18), - a series of holes (40b) distributed angularly around the central orifice in which the meshing studs (53) of the torque output shaft are inserted, and, - an external toothing (40c) arranged to cooperate by a rolling movement with a series of bosses (14f) distributed angularly on the fixing casing (14).

10. Actuating device (10) according to claim 8, wherein the meshing ring gear (51) comprises an internal toothing (51a), the receiving member (40) of the eccentric bearing then being a toothed wheel inserted in the internal toothing, and said toothed wheel comprises - a central orifice (40a) receiving the eccentric bearing (18), - an external toothing (40d) which meshes with the internal toothing (51a) of the meshing ring gear (51), and - a series of meshing studs (40e) distributed angularly around the central orifice which project axially parallel to the first axis of revolution (Y) and which cooperate with holes (61) formed in a support plate (60) attached to the fixing casing.

11. Actuating device (10) according to the preceding claim, wherein the eccentric bearing (18) is a ball bearing or a needle bearing which exerts radial support of the toothed wheel (40) on the internal teeth (51a) of the torque output shaft (50) in order to generate a rotating radial eccentric movement of the toothed wheel, the inner ring (18a) of the eccentric bearing being rotationally connected to the rotor shaft (17).

12. Actuating device (10) according to one of claims 8 to 11, wherein the torque output shaft (50) is arranged to pivot according to three adjacent angular sectors (a1, a2, a3), a first angular sector (a1), a second angular sector (a2) which is adjacent to the first angular sector, a third angular sector (a3) ​​which is adjacent to the second angular sector.

13. Transmission system (1) comprising: - a transmission drive shaft (2) comprising a first external spline (2a); - a transmission driven shaft (3) coaxial with the drive shaft comprising a second external spline (3a); - an actuating device (10) according to the preceding claim, in which the actuating cam of the torque output shaft is inserted into an axial slider (30) having a shape of revolution which partially surrounds the drive shaft (2) and the driven shaft (3), the axial slider (30) comprising at least a first spline internal connection (33) arranged to rotate the driving shaft (2) and a second internal connection spline (34) arranged to rotate the driven shaft (3), and the axial sliding member (30) is axially movable along a main axis (X) perpendicular to the first axis of revolution (Y) between two extreme positions when the torque output shaft pivots along the entire second angular sector (a 2).

14. Transmission system (1) according to the preceding claim, in which the axial slider (30) remains axially stationary in a first extreme position when the rotation of the torque output shaft is located in the first angular sector, the axial slider (30) remains axially stationary in a second extreme position when the rotation of the torque output shaft is located in the third angular sector, and the first and second internal splines (33, 34) are engaged respectively in the first external spline (2a) of the driving shaft and the second external spline (3a) of the driven shaft when the axial slider (30) is in one of the two extreme positions, this extreme position being called the second extreme coupling position.

15. Transmission system (1) according to claim 13 or 14, in which the axial slider (30) comprises a receiving housing (31) for the actuating cam of the torque output shaft formed by two surfaces (32) parallel to each other and perpendicular to the main axis (X).

16. Transmission system (1) according to the preceding claim, in which the actuating cam (20) has two contact zones (20a, 20b) bearing on the parallel surfaces (32) of the receiving housing (31) of the axial slider (30), the bearing width (L) along the main axis (X) separating the two contact zones is constant over the three angular sectors (a1, a2, a3) of rotation of the torque output shaft.

17. Transmission system (1) according to the preceding claim, in which an operating clearance (J) is defined between the bearing width (L) of the actuating cam and the distance (D) axially separating along the main axis (X) the two parallel surfaces (32) of the receiving housing, the operating clearance (J) is constant over the three angular sectors (a1, a2, a3) of rotation of the output shaft.

Images